Among those squatting and sitting in the name of "commonsense legislation" are Reps. Donna Edwards (D-MD), John Yarmuth (D-KY) and John Lewis (D-GA).

Earlier this week, Sens. Dianne Feinstein (D-CA) and Chris Murphy (D-CT) introduced four different gun control measures in the wake of the Orlando massacre. All four failed. The result drew ire from the White House, who accused the lawmakers of "cowardice."

You can follow the Democrats' sit-in on Twitter by searching for the hashtag #NoBillNoBreak.